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Message-ID: <4020E64F.8020006@lyola.com>
Date: Wed, 04 Feb 2004 15:32:15 +0300
From: Nikolay Igotti <nike@lyola.com>
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To: linux-kernel@vger.kernel.org
Subject: memmove syscall
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   Maybe this is kinda crazy (or known) idea, but why don't we create 
syscall
allowing large copies by just manipulating MMU page table, i.e.

asmlinkage long sys_memmove(void* dst, void* src, int size) {
  if ((dst & ~PAGE_SIZE) ||(src & ~PAGE_SIZE) || (size & ~PAGE_SIZE))
                return -EINVAL;

   return mmu_remap_pages(src,  dst, size / PAGE_SIZE);
}


 This could be useful for copying of large amounts of data when we know that
source not gonna be used anymore (typical example is garbage collector).
 
 Please reply directly, as I'm not on the list.


  Nikolay.